feeling movements with twins...when did you start to feel the flutters?

I am early 13 weeks now and I swear I can feel the tiniest little flutters, but didn't feel anything with my ds until about 18 weeks.

Am I just imagining things?!

I had my nuchal scan yesterday and when the sonographer was pressing down with the thingy bob I could definitely feel something having a little boogie in there! They were non stop wriggling on the screen!

Not until 22 weeks for me! First pregnancy, with two anterior placentas absorbing the kicking. I think I felt very feint flutters from about 18 weeks, but as it was my first pregnancy I didn't recognise the feeling, and even now, I don't know whether they really were movements.